JEE Main202224 Jun 2022Morning ShiftMathematicsComplex NumberActual
Let A = z ∈ C : 1 ⩽ z - 1 + i ⩽ 2 and B = z ∈ A : z - 1 - i = 1 . Then, B
Options
- Ais an empty set
- Bcontains exactly two elements
- Ccontains exactly three elements
- Dis an infinite set
Correct answer
D. is an infinite set
Step-by-step solution
z - 1 + i = 1   &   z - 1 + i = 2 represents two concentric circles with centre 1 , 1 . z - 1 - i = 1 represents a circle with centre 1 , - 1 and radius 1 A represents the region between the concentric circles with centre 1 , 1 Set B contains all points on minor arc P Q of the circle z - 1 - i = 1 . Hence, B has infinite elements.